xref: /freebsd-src/contrib/libevent/evbuffer-internal.h (revision b50261e21f39a6c7249a49e7b60aa878c98512a8)
1c43e99fdSEd Maste /*
2c43e99fdSEd Maste  * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu>
3c43e99fdSEd Maste  * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
4c43e99fdSEd Maste  *
5c43e99fdSEd Maste  * Redistribution and use in source and binary forms, with or without
6c43e99fdSEd Maste  * modification, are permitted provided that the following conditions
7c43e99fdSEd Maste  * are met:
8c43e99fdSEd Maste  * 1. Redistributions of source code must retain the above copyright
9c43e99fdSEd Maste  *    notice, this list of conditions and the following disclaimer.
10c43e99fdSEd Maste  * 2. Redistributions in binary form must reproduce the above copyright
11c43e99fdSEd Maste  *    notice, this list of conditions and the following disclaimer in the
12c43e99fdSEd Maste  *    documentation and/or other materials provided with the distribution.
13c43e99fdSEd Maste  * 3. The name of the author may not be used to endorse or promote products
14c43e99fdSEd Maste  *    derived from this software without specific prior written permission.
15c43e99fdSEd Maste  *
16c43e99fdSEd Maste  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17c43e99fdSEd Maste  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18c43e99fdSEd Maste  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19c43e99fdSEd Maste  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20c43e99fdSEd Maste  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21c43e99fdSEd Maste  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22c43e99fdSEd Maste  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23c43e99fdSEd Maste  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24c43e99fdSEd Maste  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25c43e99fdSEd Maste  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26c43e99fdSEd Maste  */
27c43e99fdSEd Maste #ifndef EVBUFFER_INTERNAL_H_INCLUDED_
28c43e99fdSEd Maste #define EVBUFFER_INTERNAL_H_INCLUDED_
29c43e99fdSEd Maste 
30c43e99fdSEd Maste #ifdef __cplusplus
31c43e99fdSEd Maste extern "C" {
32c43e99fdSEd Maste #endif
33c43e99fdSEd Maste 
34c43e99fdSEd Maste #include "event2/event-config.h"
35c43e99fdSEd Maste #include "evconfig-private.h"
36c43e99fdSEd Maste #include "event2/util.h"
37c43e99fdSEd Maste #include "event2/event_struct.h"
38c43e99fdSEd Maste #include "util-internal.h"
39c43e99fdSEd Maste #include "defer-internal.h"
40c43e99fdSEd Maste 
41c43e99fdSEd Maste /* Experimental cb flag: "never deferred."  Implementation note:
42c43e99fdSEd Maste  * these callbacks may get an inaccurate view of n_del/n_added in their
43c43e99fdSEd Maste  * arguments. */
44c43e99fdSEd Maste #define EVBUFFER_CB_NODEFER 2
45c43e99fdSEd Maste 
46c43e99fdSEd Maste #ifdef _WIN32
47c43e99fdSEd Maste #include <winsock2.h>
48c43e99fdSEd Maste #endif
49c43e99fdSEd Maste #include <sys/queue.h>
50c43e99fdSEd Maste 
51c43e99fdSEd Maste /* Minimum allocation for a chain.  We define this so that we're burning no
52c43e99fdSEd Maste  * more than 5% of each allocation on overhead.  It would be nice to lose even
53c43e99fdSEd Maste  * less space, though. */
54c43e99fdSEd Maste #if EVENT__SIZEOF_VOID_P < 8
55c43e99fdSEd Maste #define MIN_BUFFER_SIZE	512
56c43e99fdSEd Maste #else
57c43e99fdSEd Maste #define MIN_BUFFER_SIZE	1024
58c43e99fdSEd Maste #endif
59c43e99fdSEd Maste 
60c43e99fdSEd Maste /** A single evbuffer callback for an evbuffer. This function will be invoked
61c43e99fdSEd Maste  * when bytes are added to or removed from the evbuffer. */
62c43e99fdSEd Maste struct evbuffer_cb_entry {
63c43e99fdSEd Maste 	/** Structures to implement a doubly-linked queue of callbacks */
64c43e99fdSEd Maste 	LIST_ENTRY(evbuffer_cb_entry) next;
65c43e99fdSEd Maste 	/** The callback function to invoke when this callback is called.
66c43e99fdSEd Maste 	    If EVBUFFER_CB_OBSOLETE is set in flags, the cb_obsolete field is
67c43e99fdSEd Maste 	    valid; otherwise, cb_func is valid. */
68c43e99fdSEd Maste 	union {
69c43e99fdSEd Maste 		evbuffer_cb_func cb_func;
70c43e99fdSEd Maste 		evbuffer_cb cb_obsolete;
71c43e99fdSEd Maste 	} cb;
72c43e99fdSEd Maste 	/** Argument to pass to cb. */
73c43e99fdSEd Maste 	void *cbarg;
74c43e99fdSEd Maste 	/** Currently set flags on this callback. */
75c43e99fdSEd Maste 	ev_uint32_t flags;
76c43e99fdSEd Maste };
77c43e99fdSEd Maste 
78c43e99fdSEd Maste struct bufferevent;
79c43e99fdSEd Maste struct evbuffer_chain;
80c43e99fdSEd Maste struct evbuffer {
81c43e99fdSEd Maste 	/** The first chain in this buffer's linked list of chains. */
82c43e99fdSEd Maste 	struct evbuffer_chain *first;
83c43e99fdSEd Maste 	/** The last chain in this buffer's linked list of chains. */
84c43e99fdSEd Maste 	struct evbuffer_chain *last;
85c43e99fdSEd Maste 
86c43e99fdSEd Maste 	/** Pointer to the next pointer pointing at the 'last_with_data' chain.
87c43e99fdSEd Maste 	 *
88c43e99fdSEd Maste 	 * To unpack:
89c43e99fdSEd Maste 	 *
90c43e99fdSEd Maste 	 * The last_with_data chain is the last chain that has any data in it.
91c43e99fdSEd Maste 	 * If all chains in the buffer are empty, it is the first chain.
92c43e99fdSEd Maste 	 * If the buffer has no chains, it is NULL.
93c43e99fdSEd Maste 	 *
94c43e99fdSEd Maste 	 * The last_with_datap pointer points at _whatever 'next' pointer_
95*b50261e2SCy Schubert 	 * pointing at the last_with_data chain. If the last_with_data chain
96c43e99fdSEd Maste 	 * is the first chain, or it is NULL, then the last_with_datap pointer
97c43e99fdSEd Maste 	 * is &buf->first.
98c43e99fdSEd Maste 	 */
99c43e99fdSEd Maste 	struct evbuffer_chain **last_with_datap;
100c43e99fdSEd Maste 
101c43e99fdSEd Maste 	/** Total amount of bytes stored in all chains.*/
102c43e99fdSEd Maste 	size_t total_len;
103c43e99fdSEd Maste 
104c43e99fdSEd Maste 	/** Number of bytes we have added to the buffer since we last tried to
105c43e99fdSEd Maste 	 * invoke callbacks. */
106c43e99fdSEd Maste 	size_t n_add_for_cb;
107c43e99fdSEd Maste 	/** Number of bytes we have removed from the buffer since we last
108c43e99fdSEd Maste 	 * tried to invoke callbacks. */
109c43e99fdSEd Maste 	size_t n_del_for_cb;
110c43e99fdSEd Maste 
111c43e99fdSEd Maste #ifndef EVENT__DISABLE_THREAD_SUPPORT
112c43e99fdSEd Maste 	/** A lock used to mediate access to this buffer. */
113c43e99fdSEd Maste 	void *lock;
114c43e99fdSEd Maste #endif
115c43e99fdSEd Maste 	/** True iff we should free the lock field when we free this
116c43e99fdSEd Maste 	 * evbuffer. */
117c43e99fdSEd Maste 	unsigned own_lock : 1;
118c43e99fdSEd Maste 	/** True iff we should not allow changes to the front of the buffer
119c43e99fdSEd Maste 	 * (drains or prepends). */
120c43e99fdSEd Maste 	unsigned freeze_start : 1;
121c43e99fdSEd Maste 	/** True iff we should not allow changes to the end of the buffer
122c43e99fdSEd Maste 	 * (appends) */
123c43e99fdSEd Maste 	unsigned freeze_end : 1;
124c43e99fdSEd Maste 	/** True iff this evbuffer's callbacks are not invoked immediately
125c43e99fdSEd Maste 	 * upon a change in the buffer, but instead are deferred to be invoked
126c43e99fdSEd Maste 	 * from the event_base's loop.	Useful for preventing enormous stack
127c43e99fdSEd Maste 	 * overflows when we have mutually recursive callbacks, and for
128c43e99fdSEd Maste 	 * serializing callbacks in a single thread. */
129c43e99fdSEd Maste 	unsigned deferred_cbs : 1;
130c43e99fdSEd Maste #ifdef _WIN32
131c43e99fdSEd Maste 	/** True iff this buffer is set up for overlapped IO. */
132c43e99fdSEd Maste 	unsigned is_overlapped : 1;
133c43e99fdSEd Maste #endif
134c43e99fdSEd Maste 	/** Zero or more EVBUFFER_FLAG_* bits */
135c43e99fdSEd Maste 	ev_uint32_t flags;
136c43e99fdSEd Maste 
137c43e99fdSEd Maste 	/** Used to implement deferred callbacks. */
138c43e99fdSEd Maste 	struct event_base *cb_queue;
139c43e99fdSEd Maste 
140c43e99fdSEd Maste 	/** A reference count on this evbuffer.	 When the reference count
141c43e99fdSEd Maste 	 * reaches 0, the buffer is destroyed.	Manipulated with
142c43e99fdSEd Maste 	 * evbuffer_incref and evbuffer_decref_and_unlock and
143c43e99fdSEd Maste 	 * evbuffer_free. */
144c43e99fdSEd Maste 	int refcnt;
145c43e99fdSEd Maste 
146c43e99fdSEd Maste 	/** A struct event_callback handle to make all of this buffer's callbacks
147c43e99fdSEd Maste 	 * invoked from the event loop. */
148c43e99fdSEd Maste 	struct event_callback deferred;
149c43e99fdSEd Maste 
150c43e99fdSEd Maste 	/** A doubly-linked-list of callback functions */
151c43e99fdSEd Maste 	LIST_HEAD(evbuffer_cb_queue, evbuffer_cb_entry) callbacks;
152c43e99fdSEd Maste 
153c43e99fdSEd Maste 	/** The parent bufferevent object this evbuffer belongs to.
154c43e99fdSEd Maste 	 * NULL if the evbuffer stands alone. */
155c43e99fdSEd Maste 	struct bufferevent *parent;
156c43e99fdSEd Maste };
157c43e99fdSEd Maste 
158c43e99fdSEd Maste #if EVENT__SIZEOF_OFF_T < EVENT__SIZEOF_SIZE_T
159c43e99fdSEd Maste typedef ev_ssize_t ev_misalign_t;
160c43e99fdSEd Maste #define EVBUFFER_CHAIN_MAX ((size_t)EV_SSIZE_MAX)
161c43e99fdSEd Maste #else
162c43e99fdSEd Maste typedef ev_off_t ev_misalign_t;
163c43e99fdSEd Maste #if EVENT__SIZEOF_OFF_T > EVENT__SIZEOF_SIZE_T
164c43e99fdSEd Maste #define EVBUFFER_CHAIN_MAX EV_SIZE_MAX
165c43e99fdSEd Maste #else
166c43e99fdSEd Maste #define EVBUFFER_CHAIN_MAX ((size_t)EV_SSIZE_MAX)
167c43e99fdSEd Maste #endif
168c43e99fdSEd Maste #endif
169c43e99fdSEd Maste 
170c43e99fdSEd Maste /** A single item in an evbuffer. */
171c43e99fdSEd Maste struct evbuffer_chain {
172c43e99fdSEd Maste 	/** points to next buffer in the chain */
173c43e99fdSEd Maste 	struct evbuffer_chain *next;
174c43e99fdSEd Maste 
175c43e99fdSEd Maste 	/** total allocation available in the buffer field. */
176c43e99fdSEd Maste 	size_t buffer_len;
177c43e99fdSEd Maste 
178c43e99fdSEd Maste 	/** unused space at the beginning of buffer or an offset into a
179c43e99fdSEd Maste 	 * file for sendfile buffers. */
180c43e99fdSEd Maste 	ev_misalign_t misalign;
181c43e99fdSEd Maste 
182c43e99fdSEd Maste 	/** Offset into buffer + misalign at which to start writing.
183c43e99fdSEd Maste 	 * In other words, the total number of bytes actually stored
184c43e99fdSEd Maste 	 * in buffer. */
185c43e99fdSEd Maste 	size_t off;
186c43e99fdSEd Maste 
187c43e99fdSEd Maste 	/** Set if special handling is required for this chain */
188c43e99fdSEd Maste 	unsigned flags;
189c43e99fdSEd Maste #define EVBUFFER_FILESEGMENT	0x0001  /**< A chain used for a file segment */
190c43e99fdSEd Maste #define EVBUFFER_SENDFILE	0x0002	/**< a chain used with sendfile */
191c43e99fdSEd Maste #define EVBUFFER_REFERENCE	0x0004	/**< a chain with a mem reference */
192c43e99fdSEd Maste #define EVBUFFER_IMMUTABLE	0x0008	/**< read-only chain */
193c43e99fdSEd Maste 	/** a chain that mustn't be reallocated or freed, or have its contents
194c43e99fdSEd Maste 	 * memmoved, until the chain is un-pinned. */
195c43e99fdSEd Maste #define EVBUFFER_MEM_PINNED_R	0x0010
196c43e99fdSEd Maste #define EVBUFFER_MEM_PINNED_W	0x0020
197c43e99fdSEd Maste #define EVBUFFER_MEM_PINNED_ANY (EVBUFFER_MEM_PINNED_R|EVBUFFER_MEM_PINNED_W)
198c43e99fdSEd Maste 	/** a chain that should be freed, but can't be freed until it is
199c43e99fdSEd Maste 	 * un-pinned. */
200c43e99fdSEd Maste #define EVBUFFER_DANGLING	0x0040
201c43e99fdSEd Maste 	/** a chain that is a referenced copy of another chain */
202c43e99fdSEd Maste #define EVBUFFER_MULTICAST	0x0080
203c43e99fdSEd Maste 
204c43e99fdSEd Maste 	/** number of references to this chain */
205c43e99fdSEd Maste 	int refcnt;
206c43e99fdSEd Maste 
207c43e99fdSEd Maste 	/** Usually points to the read-write memory belonging to this
208c43e99fdSEd Maste 	 * buffer allocated as part of the evbuffer_chain allocation.
209c43e99fdSEd Maste 	 * For mmap, this can be a read-only buffer and
210c43e99fdSEd Maste 	 * EVBUFFER_IMMUTABLE will be set in flags.  For sendfile, it
211c43e99fdSEd Maste 	 * may point to NULL.
212c43e99fdSEd Maste 	 */
213c43e99fdSEd Maste 	unsigned char *buffer;
214c43e99fdSEd Maste };
215c43e99fdSEd Maste 
216c43e99fdSEd Maste /** callback for a reference chain; lets us know what to do with it when
217c43e99fdSEd Maste  * we're done with it. Lives at the end of an evbuffer_chain with the
218c43e99fdSEd Maste  * EVBUFFER_REFERENCE flag set */
219c43e99fdSEd Maste struct evbuffer_chain_reference {
220c43e99fdSEd Maste 	evbuffer_ref_cleanup_cb cleanupfn;
221c43e99fdSEd Maste 	void *extra;
222c43e99fdSEd Maste };
223c43e99fdSEd Maste 
224c43e99fdSEd Maste /** File segment for a file-segment chain.  Lives at the end of an
225c43e99fdSEd Maste  * evbuffer_chain with the EVBUFFER_FILESEGMENT flag set.  */
226c43e99fdSEd Maste struct evbuffer_chain_file_segment {
227c43e99fdSEd Maste 	struct evbuffer_file_segment *segment;
228c43e99fdSEd Maste #ifdef _WIN32
229c43e99fdSEd Maste 	/** If we're using CreateFileMapping, this is the handle to the view. */
230c43e99fdSEd Maste 	HANDLE view_handle;
231c43e99fdSEd Maste #endif
232c43e99fdSEd Maste };
233c43e99fdSEd Maste 
234c43e99fdSEd Maste /* Declared in event2/buffer.h; defined here. */
235c43e99fdSEd Maste struct evbuffer_file_segment {
236c43e99fdSEd Maste 	void *lock; /**< lock prevent concurrent access to refcnt */
237c43e99fdSEd Maste 	int refcnt; /**< Reference count for this file segment */
238c43e99fdSEd Maste 	unsigned flags; /**< combination of EVBUF_FS_* flags  */
239c43e99fdSEd Maste 
240c43e99fdSEd Maste 	/** What kind of file segment is this? */
241c43e99fdSEd Maste 	unsigned can_sendfile : 1;
242c43e99fdSEd Maste 	unsigned is_mapping : 1;
243c43e99fdSEd Maste 
244c43e99fdSEd Maste 	/** The fd that we read the data from. */
245c43e99fdSEd Maste 	int fd;
246c43e99fdSEd Maste 	/** If we're using mmap, this is the raw mapped memory. */
247c43e99fdSEd Maste 	void *mapping;
248c43e99fdSEd Maste #ifdef _WIN32
249c43e99fdSEd Maste 	/** If we're using CreateFileMapping, this is the mapping */
250c43e99fdSEd Maste 	HANDLE mapping_handle;
251c43e99fdSEd Maste #endif
252c43e99fdSEd Maste 	/** If we're using mmap or IO, this is the content of the file
253c43e99fdSEd Maste 	 * segment. */
254c43e99fdSEd Maste 	char *contents;
255c43e99fdSEd Maste 	/** Position of this segment within the file. */
256c43e99fdSEd Maste 	ev_off_t file_offset;
257c43e99fdSEd Maste 	/** If we're using mmap, this is the offset within 'mapping' where
258c43e99fdSEd Maste 	 * this data segment begins. */
259c43e99fdSEd Maste 	ev_off_t mmap_offset;
260c43e99fdSEd Maste 	/** The length of this segment. */
261c43e99fdSEd Maste 	ev_off_t length;
262c43e99fdSEd Maste 	/** Cleanup callback function */
263c43e99fdSEd Maste 	evbuffer_file_segment_cleanup_cb cleanup_cb;
264c43e99fdSEd Maste 	/** Argument to be pass to cleanup callback function */
265c43e99fdSEd Maste 	void *cleanup_cb_arg;
266c43e99fdSEd Maste };
267c43e99fdSEd Maste 
268c43e99fdSEd Maste /** Information about the multicast parent of a chain.  Lives at the
269c43e99fdSEd Maste  * end of an evbuffer_chain with the EVBUFFER_MULTICAST flag set.  */
270c43e99fdSEd Maste struct evbuffer_multicast_parent {
271c43e99fdSEd Maste 	/** source buffer the multicast parent belongs to */
272c43e99fdSEd Maste 	struct evbuffer *source;
273c43e99fdSEd Maste 	/** multicast parent for this chain */
274c43e99fdSEd Maste 	struct evbuffer_chain *parent;
275c43e99fdSEd Maste };
276c43e99fdSEd Maste 
277c43e99fdSEd Maste #define EVBUFFER_CHAIN_SIZE sizeof(struct evbuffer_chain)
278c43e99fdSEd Maste /** Return a pointer to extra data allocated along with an evbuffer. */
279c43e99fdSEd Maste #define EVBUFFER_CHAIN_EXTRA(t, c) (t *)((struct evbuffer_chain *)(c) + 1)
280c43e99fdSEd Maste 
281c43e99fdSEd Maste /** Assert that we are holding the lock on an evbuffer */
282c43e99fdSEd Maste #define ASSERT_EVBUFFER_LOCKED(buffer)			\
283c43e99fdSEd Maste 	EVLOCK_ASSERT_LOCKED((buffer)->lock)
284c43e99fdSEd Maste 
285c43e99fdSEd Maste #define EVBUFFER_LOCK(buffer)						\
286c43e99fdSEd Maste 	do {								\
287c43e99fdSEd Maste 		EVLOCK_LOCK((buffer)->lock, 0);				\
288c43e99fdSEd Maste 	} while (0)
289c43e99fdSEd Maste #define EVBUFFER_UNLOCK(buffer)						\
290c43e99fdSEd Maste 	do {								\
291c43e99fdSEd Maste 		EVLOCK_UNLOCK((buffer)->lock, 0);			\
292c43e99fdSEd Maste 	} while (0)
293c43e99fdSEd Maste #define EVBUFFER_LOCK2(buffer1, buffer2)				\
294c43e99fdSEd Maste 	do {								\
295c43e99fdSEd Maste 		EVLOCK_LOCK2((buffer1)->lock, (buffer2)->lock, 0, 0);	\
296c43e99fdSEd Maste 	} while (0)
297c43e99fdSEd Maste #define EVBUFFER_UNLOCK2(buffer1, buffer2)				\
298c43e99fdSEd Maste 	do {								\
299c43e99fdSEd Maste 		EVLOCK_UNLOCK2((buffer1)->lock, (buffer2)->lock, 0, 0);	\
300c43e99fdSEd Maste 	} while (0)
301c43e99fdSEd Maste 
302c43e99fdSEd Maste /** Increase the reference count of buf by one. */
303c43e99fdSEd Maste void evbuffer_incref_(struct evbuffer *buf);
304c43e99fdSEd Maste /** Increase the reference count of buf by one and acquire the lock. */
305c43e99fdSEd Maste void evbuffer_incref_and_lock_(struct evbuffer *buf);
306c43e99fdSEd Maste /** Pin a single buffer chain using a given flag. A pinned chunk may not be
307c43e99fdSEd Maste  * moved or freed until it is unpinned. */
308c43e99fdSEd Maste void evbuffer_chain_pin_(struct evbuffer_chain *chain, unsigned flag);
309c43e99fdSEd Maste /** Unpin a single buffer chain using a given flag. */
310c43e99fdSEd Maste void evbuffer_chain_unpin_(struct evbuffer_chain *chain, unsigned flag);
311c43e99fdSEd Maste /** As evbuffer_free, but requires that we hold a lock on the buffer, and
312c43e99fdSEd Maste  * releases the lock before freeing it and the buffer. */
313c43e99fdSEd Maste void evbuffer_decref_and_unlock_(struct evbuffer *buffer);
314c43e99fdSEd Maste 
315c43e99fdSEd Maste /** As evbuffer_expand, but does not guarantee that the newly allocated memory
316c43e99fdSEd Maste  * is contiguous.  Instead, it may be split across two or more chunks. */
317c43e99fdSEd Maste int evbuffer_expand_fast_(struct evbuffer *, size_t, int);
318c43e99fdSEd Maste 
319c43e99fdSEd Maste /** Helper: prepares for a readv/WSARecv call by expanding the buffer to
320c43e99fdSEd Maste  * hold enough memory to read 'howmuch' bytes in possibly noncontiguous memory.
321c43e99fdSEd Maste  * Sets up the one or two iovecs in 'vecs' to point to the free memory and its
322c43e99fdSEd Maste  * extent, and *chainp to point to the first chain that we'll try to read into.
323c43e99fdSEd Maste  * Returns the number of vecs used.
324c43e99fdSEd Maste  */
325c43e99fdSEd Maste int evbuffer_read_setup_vecs_(struct evbuffer *buf, ev_ssize_t howmuch,
326c43e99fdSEd Maste     struct evbuffer_iovec *vecs, int n_vecs, struct evbuffer_chain ***chainp,
327c43e99fdSEd Maste     int exact);
328c43e99fdSEd Maste 
329c43e99fdSEd Maste /* Helper macro: copies an evbuffer_iovec in ei to a win32 WSABUF in i. */
330c43e99fdSEd Maste #define WSABUF_FROM_EVBUFFER_IOV(i,ei) do {		\
331c43e99fdSEd Maste 		(i)->buf = (ei)->iov_base;		\
332c43e99fdSEd Maste 		(i)->len = (unsigned long)(ei)->iov_len;	\
333c43e99fdSEd Maste 	} while (0)
334c43e99fdSEd Maste /* XXXX the cast above is safe for now, but not if we allow mmaps on win64.
335c43e99fdSEd Maste  * See note in buffer_iocp's launch_write function */
336c43e99fdSEd Maste 
337c43e99fdSEd Maste /** Set the parent bufferevent object for buf to bev */
338c43e99fdSEd Maste void evbuffer_set_parent_(struct evbuffer *buf, struct bufferevent *bev);
339c43e99fdSEd Maste 
340c43e99fdSEd Maste void evbuffer_invoke_callbacks_(struct evbuffer *buf);
341c43e99fdSEd Maste 
342c43e99fdSEd Maste 
343c43e99fdSEd Maste int evbuffer_get_callbacks_(struct evbuffer *buffer,
344c43e99fdSEd Maste     struct event_callback **cbs,
345c43e99fdSEd Maste     int max_cbs);
346c43e99fdSEd Maste 
347c43e99fdSEd Maste #ifdef __cplusplus
348c43e99fdSEd Maste }
349c43e99fdSEd Maste #endif
350c43e99fdSEd Maste 
351c43e99fdSEd Maste #endif /* EVBUFFER_INTERNAL_H_INCLUDED_ */
352